This T32 is submitted by the Columbia University (CU) School of Social Work (SSW) and the Department of Sociomedical Sciences at the Mailman School of Public Health (SMS/MSPH). It proposes to train the next generation of pre- and post-doctoral scholars in the prevention, treatment, and care of HIV and drug abuse among individuals in the criminal justice system. This training application places a strong emphasis on individuals involved in alternatives to incarceration and community supervision (e.g., diversion programs, probation, and community and drug courts) who are affected by health disparities. This training program will provide: (1) interdisciplinary research instruction and training for pre doctoral students and post-doctoral fellows on the intersecting issues of drug abuse, HIV and the criminal justice system; and (2) hands-on, mentored experience conducting independent research in the study of HIV and drug abuse prevention, treatment, and care for criminal justice-involved populations. This program is designed to strengthen the pool of researchers by increasing the diversity of academic backgrounds-e.g., social work, public health, medicine, sociology, political science, anthropology-and those from underrepresented populations-e.g., underrepresented minorities (URM), people with disabilities and individuals from disadvantaged backgrounds. The faculty who will participate in this proposed training program are drawn from a number of CU departments and schools as well as other universities and research centers. Participating faculty are leaders in HIV, drug abuse, and criminal justice fields, with strong trac records of support from NIDA and NIMH and other institutes. They are also well-qualified to provide training, as evidenced by their strong records of mentorship of pre-doctoral students and postdoctoral fellows. Each year, the training program will select and appoint pre-doctoral trainees who will be supported for up to 5 years, and 2 postdoctoral fellows, who will be supported for up to 3 years. At full capacity, the program will support 4 pre-doctoral students and 4 post-doctoral fellows per year. Altogether, the program is anticipated to support a total of 6-8 pre-doctoral trainees and 8-10 post-doctoral trainees over the 5-year funding period. Thus, the program will add a substantial number of highly qualified new scholars to the field focusing on HIV and drug abuse among criminal justice-involved populations. Dr. Nabila El-Bassel (SSW) and Dr. Lisa Metsch (SMS/MSPH) will serve as PIs/Co-Directors for the proposed training program, which provides an opportunity for two noted and distinguished scientists to collaborate and lead this initiative. They each contribute over 20 years of experience in the HIV, drug abuse, and criminal justice fields.